I believe this is a carrier option as users in America can access it. I'll post a link to what I mean.
But this option is not available on Rogers. If say someone with iMessage sends a message to 10 other people with iMessage you are screwed and stuck in that huge chat and get like 40+ texts a minute. No way of leaving the chat. If you delete it, then it comes back once someone writes a new message.
Bell, Telus, Virgin & Rogers & Fido do NOT offer this. This could be a issue with Apple Canada & the carriers. This could be that the carriers do not want it OR Apple Canada does not want it for us here. No one will know the real truth here on why we do not get this option.
Believe me, Rogers won't give any answers out. Many ask for answers and yet Rogers doesn't respond.
It is a carrier thing yet you can't get stuck with " ATT". None of the Canadian carriers have the option for " Leave Group messages" on the iPhone. Something else is in play here. While I would like it as well, its not only Rogers.